The invention relates to a monocrystalline MnZn-ferroferrite material particularly suitable for use in a magnetic head. The invention also relates to a magnetic head manufactured from this material. This type of magnetic head is used for recording, erasing and playing-back information, for example, in audio and video apparatus.
MnZn-ferroferrite material is known from European Patent Application, publication number 86005. The magnetic material described in this European Application corresponds to the formula EQU Mn.sub.a Zn.sub.b Fe.sub.c.sup.II Fe.sub.2.sup.III O.sub.4,
wherein
0.ltoreq.a&lt;0.55; PA1 0.06.ltoreq.b&lt;0.4 and PA1 0.25.ltoreq.c&lt;0.9 PA1 0.25&lt;a&lt;0.48; PA1 0.50&lt;b&lt;0.60; PA1 0.02&lt;c&lt;0.15; PA1 a+b+c=1.
while it further holds that a+b+c=1. This known material has a number of good soft-magnetic properties, for example, a high saturation magnetization B.sub.s and a high magnetic permeability .mu.. It has been established, however, that this material suffers from the disadvantage that the absolute value of the two magnetostriction constants .lambda..sub.100 and .lambda..sub.111 is high (.lambda..sub.111 &gt;15.10.sup.-6 and .lambda..sub.100 &lt;-5.10.sup.-6). The magnetostriction contributes to the so-called "rubbing noise" via the inverse magnetostriction effect. This contribution to the rubbing noise is proportional to the magnitude of the absolute values of the magnetostriction constants. The frequency-dependent rubbing noise is considerable in the MHz-range. Video heads are used in said frequency range (4-30 MHz).